Polygonally wrapped sleeve, and methods and devices for making same

Abstract

This invention relates to packaging "sleeves", or multi-sided, tubular structures which may be used for packaging articles, as blanks for boxes, or the like, which are made from multiple layers of spirally wrapped strips of paper, fabric, or the like; which sleeves may have discrete corners at the junctures of their sidewalls, which corners may be permanent where rididity is desired, or foldable so that the sleeves may be flattened for storage and/or shipment. Such sleeves may be made by apparatus, and/or utilizing methods, in accordance with the present invention, which contemplates the formation of a subtantially cylindrical core over a cylindrical spindle, and transfering the core to axially oriented lines of rollers which are oriented radially to the axis of the spindle at sequentially increasing distances therefrom, whereby the sleeve, while still softened from the application of glue to its constituent layers, may be permanently distorted into its desired multi-sided, multi-cornered configuration, with desired radii at the corners and such grooves as may be desired to augment hinging to facilitate flattening of the sleeves.

I claim: 
     
       1. A method for making substantially flatsided polygonal tubular packaging sleeves comprising the steps of applying to selected strips of material, a bonding material which causes the material of said strips to be softened and deformable until said bonding material sets,   wrapping said strips of material about a stationary spindle in overlayed relationship to each other to form a tube,   causing said tube, while the strips of material thereof are in the bonding material-softened state, to move off of said spindle over at least two rows of rollers, the planes of rotation of which rollers are oriented substantially radially with respect to the axis of said spindle, said rollers being so positioned with respect to said spindle that the inside of tubes passing thereover will be borne upon by said rollers to provide bearing surfaces over which longitudinally oriented corners will be produced in said tubes.   
     
     
       2. The method described in claim 1 wherein said tube is moved over rolls which are positioned progressively further outward from said axis proceeding in the direction in which said tube is caused to move. 
     
     
       3. The method described in claim 2 including the step of deforming at least some of the constituent layers of material of said tube by means of said rollers acting upon said layers while they are still soft from the application of said bonding material thereto. 
     
     
       4. The method described in claim 3 including the step of impressing at least one permanent groove into the walls of said sleeve, oriented longitudinally with respect thereto in the region of an edge of said sleeve, while the material forming said sleeve is still soft from the application of said bonding material thereto. 
     
     
       5. The method described in claim 4 wherein each of said grooves is positioned inside said sleeve. 
     
     
       6. The method described in claim 5 including the step of impressing at least one permanent groove into the outside of the walls of said sleeve substantially opposite a groove on the inside thereof. 
     
     
       7. The method described in claim 6 wherein said step of impressing said grooves comprises a milling process. 
     
     
       8. The method described in claim 5 wherein said step of impressing said grooves comprises a milling process. 
     
     
       9. The method described in claim 4 wherein said step of impressing said grooves comprises a milling process. 
     
     
       10. The method described in claim 4 wherein said step of forming said grooves comprises subjecting said sleeve to consecutive, radially expanding, groove forming devices. 
     
     
       11. The method described in claim 4 wherein each of said grooves are impressed in said sleeve as a last process step. 
     
     
       12. The method described in claim 2 wherein said rollers in all of said rows are equidistant radially from the axis of said spindle at progressively increasing distances from said axis in the direction of travel of said sleeves.